Detergent composition and method of preparing same



Patented Dec. 24, 1946 DETERGENT COMPOSITION AND METHOD OF PREPARING SAME Frederick G. Bersworth, Verona, N. J.

No Drawing. Application July- 2'7, 1945,

Serial No. 607,481

16 Claims. 252-117) This invention relates to detergents and detergent compositions and has for its object the provision of a detergent that is soluble in water and is miscible with alkali metal fatty acid soap compounds to form detergent compositions adapted for use in saline and hard waters and a method of producing the said detergent product.

Another object is to provide a soap composition suitable for use in hard and saline (sea) waters.

A further object is to provide a detergent composition of matter consisting of the reaction product of a polyalcohol, such as glycerine and an alkali metal salt of an amino polyacetic acid, such as the tetrasodium salt of ethylene diamine tetracarboxylic acid.

Other objects will be apparent as the inve is more fully hereinafter disclosed.

In accordance with these objects I have discovered that by heating together a polyalcohol and the alkali metal salt of an amino polyacetic acid, each compound being either in the anhydrous state or in aqueous solution, to a temperature and for a time interval required to obtain a substantially anhydrous reaction product, the resultant reaction product is a detergent soluble in water and having strong foamin roperties in hard and saline or sea water and the additional property of being substantially non-reactive with soluble salts in hard and saline water to form insoluble salts therewith. I have further discovered that the reaction product is miscible with alkali metal fatty acid soap compounds in all proportions up to equal proportions without interfering with the normal bar, flake and powder forming properties of the soap compounds and that when added to, or incorporated in, said soap compounds imparts thereto the property of foaming in hard and saline (sea) water and inhibits or prevents the reaction of the said soap compounds with tion soluble salts in the water to form insoluble soap v compounds.

The relative proportions of the two compounds may be varied widely without essential departure from the present invention from approximately equal amounts by weight to a considerable excess of one constituent over the other constituent. In other words, the relative portions of the hydroxyl groups of one and the sodium atoms of the other may vary from a large excess of either to the other.

By the term polyalcohol is meant any polyalcohol containing at least two but not more than six alcoholic (hydroxyl) groups. Typical examples of such polyalcohols are glycerine, mannitol, sorbitol and triethanol amine.

By the term alkali metal salt of an amino polyacetic acid" is meant an alkali metal salt of an amino poiyacetic acid conforming to the formula:

N-R noes-chi wherein R is selected from the group consisting of Example -CH2- C 0 0H yc e) C H:- C 0 0 H 0 H:- CH:-

CH:- C 0 0H (Ethylene diamine tetracarboxylic acid) CH:- C 0 OH.

-A(NH--A) -N CH, C 0 0H (Diethylene triamine tetracarboxylic acid) and CHrCOOH --A--(NA)N cnrcoon Hz-COOH).

(Diethylene triamine pentacarboxylic acid) in which in is zero and any positive integer and A is a member of the group consisting of alkylene and hydroxyalkylene.

Representative examples of the amino poly acids are ethylene diamine tetraacetic acid, propylene diamine tetraacetic acid, diamino propanol tetraacetic acid, diethylene triamino polyacetic acid, dipropylene triamino polvacetic acid,'.

and triethylene tetramino polyacetic acid. 7

The detergent reaction product of the present invention is made by heating the alkali metal salt of the polyacetic acid with at least 15%, by weight, of the polyalcohol to elevated temperatures above the boiling point of water with thorough agitation and fOr an extended time interval required to remove water to the extent re- It is not known whether the reaction product of the present invention is a chemical compound or a mixture of chemical compounds. It is known, however, that a mechanical mixture of the two reactants in the same relative proportions in either the hydrous or anhydrous state does not exhibit the properties of a detergent when added to hard and saline water and is not miscible with the alkali metal fatty acid soap compounds. By heating the mechanical mixture to elevated temperatures above the vaporization temperature of water for a time interval requiredto obtain a substantially homogeneous liquid phase reaction product, a chemical reaction occurs that results in the formation of a highly water soluble compound or mixture of compounds which have strongly detergent properties, strong deionizing properties and strong electrolyte carrying properties, which render the reaction product freely miscible with alkali metal fatty acid soap compounds in all proportions up to equal amounts, by weight, to form soap mixtures of strong sudsing and foaming properties in hard and saline water without forming insoluble soap compounds with the soluble salts in said hard and saline water.

As specific examples of the practice of the present invention with various polyalcohols and various salts of amino polyacetic acids the following are given:

I. Two (2) molar weights of the tetrasodium salt of ethylene diamine tetraacetic acid (760 grams), dissolved in 1 /2 liters (1500 grams) of water, are heated to the boiling point of the solution in a container open to the atmosphere. Three hundred (300) grams of mannitol (CH2OH(CHOH) 4CH2OH) are added to the boiling solution and boiling of the solution is continued until approximately 1200 grams of water have been removed by evaporation from the solution.

The resultant clear liquid reaction product, on cooling to room temperatures, has the consistency of cold glycerine, is highly soluble in water, has excellent detergent properties with good foaming properties in hard and saline water and does not react with soluble salts and electrolytes in aqueous solutions to form insoluble compounds therewith. The reaction product is miscible with alkali metal fatty acid soap compounds in all,

proportions up to equal amounts by weight to form a detergent composition adapted to be formed into bar, flake and powder which is free foaming in hard and saline water and non-reactive with soluble salts and electrolytes in the hard and saline water to form insoluble soap compounds therewith.

II. Where sorbitol in an amount approximating 300 grams is substituted for mannitol in the above Example I, a closely similar reaction product is obtained exhibiting substantially the same properties.

III. Where glycerine is substituted for mannitol in the above Example I, I prefer to employ about 440 grams of the glycerine for each 200 grams of the polyacetic acid salt, and to employ the salt in its substantially anhydrous condition. With this modification of the method of Example I it is necessary to heat the glycerine-salt mixture to temperatures approximating 140-145 C. with good agitation for an extended period of time approximating hours to form the reaction product of the present invention. So heated, the reaction product on cooling to room temperatures has the consistency of clear, soft soap but at lower temperatures tends to congeal to a product resembling putty.

Like the previous products described, however, the reaction product is highly soluble in water, has free-foaming properties in hard and saline waters without forming insoluble compounds with the soluble salts and electrolytes in the water, and is a strong detergent. The product is freely miscible in all proportions up to equal weights with alkali metal fatty acid soap compounds to impart these desirable properties to such soap compounds without interfering with the desired bar, flake and powder forming properties ,of the said soap compounds.

IV. When 380 grams of the tetrasodium salt of ethylene diamine tetraacetic acid in 500 c. c. of water and 200 grams of triethanol amine are heated to temperatures above the boiling point of water until the major portion of the water is removed by vaporization, a reaction product 15 obtained which is a heavy, clear yellow liquid when hot and a waxy solid when cooled to atmospheric temperatures. This reaction product evidences the same properties in aqueous solution as the other products above described and imparts these properties to alkali metal fatty acid soap compounds with which it is miscible in all proportions up to about equal weights.

V. Where the tetrasodium salt of propylene diamine tetraacetic acid is substituted for the tetrasodium salt of ethylene diamine tetraacetic acid in equivalent amounts in any of the above examples, lower viscosity reaction products are obtained which otherwise evidence the same properties.

VI. Where the tetra-sodium salt of diamino propanol tetraacetic acid is substituted for the tetrasodium salt of ethylene diamine tetraacetic acid, in any of the above examples in equivalent amounts, lower viscosity reaction products evidencing the same properties are also obtained.

VII. Where the sodium salt of diethylene triamine polyacetic acid is substituted for the tetrasodium salt of ethylene diamine polyacetic acid in Example I in equivalent amounts and glycerine is substituted for mannitol in equivalent amounts, and the heating is continued until at least of the water present is removed by evaporation, a reaction product is obtained which on cooling to room temperatures is waxy in nature. This product, however, is freely soluble in water and in the liquid phase is freely miscible with alkali metal soap compounds, and evidences all of the desirable properties above noted.

VIlI.- The substitution of the sodium salt of dipropylene triainine polyacetic acid for the polyacetic acid salt of Example VII produces a reaction product closely resembling the reaction product obtained'in Example VI.

IX. Where the tetrasodium salt of ethylene diamine tetraacetic acid and glycerine are reacted in aqueous solution, as in Example I instead of as in Example III, and the amount of water removed by vaporization is anywhere within the range 40-90% of that present in the solution a reaction product liquid at C. but solidifying to a putty-like semi-crystalline solid at room temperatures is obtained where the reacting constituents are present in approximately equal amounts. The amount of water present in the reaction product varies the kind of solid obtained at room temperatures, but the solid appears capable of holding large amounts of water in crystalproduct while in its liquid phase with fatty acid soap compounds while in their liquid phase. Where the reaction product is not desired for admixture with fatty acid soap compounds, however, the amount of water present may be varied v widely without essential departure from the present invention, depending upon whether a reaction product in the solid or liquid phase is desired. In all such reactions conducted in the presence of water, however, an extended time interval of heating at temperatures approximating the boiling point of water appears necessary to induce or promote the formation of the reaction product of the present invention. In most instances, a time interval of heating at least approximating hours appears to be required, although shorter or longer time intervals may be employed without essential departure from the invention.

Where the two reactants in the non-aqueous phase are brought together, higher temperatures than the boiling point of water normally are required and precautionary measures to prevent the loss of the more volatile constituent must be taken, as by the use of a reflux condenser. For this reason, the performance of the reaction in the presence of water at the boiling point of water is preferred and ordinarily heating is continued until the water content of the mixture is reduced to an amount not over about 20% and to an amount producing a substantially anhydrous liquid phase at the temperature of heating. This normally requires the use of temperatures above 100 C. as the water content falls below 20% with refluxing to prevent the loss of volatile constituents as the product approaches the substantially water-free state.

All of the above noted reaction products are freely soluble in water, and evidence free foaming properties with strong detergent properties evenin relatively hard or strong electrolyte-carrying solutions, such as sea water, without the precipitation of insoluble salts or compounds by reaction with the salts and electrolytes present in the water. All of the reaction products in the liquid anhydrous phase are freely miscible in all proportions and to equal amounts by weight with alkali metal fatty acid soap compounds in their liquid phase without detriment to the bar, flake or powder forming properties of the soap compounds and impart to such soap mixtures strong foaming properties in hard and electrolyte-carrying water without the formation of insoluble soap compounds.

6 reaction product of an aliphatic polyhydroxy characterized by being highly soluble in water, by v being non-reactive with salts and electrolytes present in the water to form insoluble compounds therewith, by being a strong detergent in aqueous solutions, and by being miscible in all proportions up to equal amounts by weight with alkali metal fatty acid soap compounds without detriment to the bar, flake and powder iorming properties of the said soap compounds, by imparting to said soap compounds stron foaming properties in the presence of dissolve salts and electrolytes without the formation of insoluble soap compounds therewith.

2. A product of manufacture consisting of a detergent consisting of a reaction product between analiphatic polyhydroxy alcohol and a neutral alkali metal salt of a lower alkyl amino polyacetic acid, the two said compounds being present in the reaction product in the relative amounts ranging from approximately equal amounts up to and including a large excess of either constituent, said reaction product having been formed by heating said salt and alcohol together in aqueous solution to temperatures with in the range 115-200 C. for an extended time interval effective to vaporize the major portion of the water therefrom.

3. The product of claim 2, said product being in its substantially anhydrous phase.

4. The product of claim 2 in its substantially anhydrous phase in admixture with alkali metal fatty acid soap compounds in amounts up to approximately equal amounts, by weight.

5. The product of claim 2, wherein said alcohol consists of glycerine.

6. The product of claim 2, wherein said alkali metal salt of an amino polyacetic acid consists of the tetrasodium salt of ethylene diamine tetraacetic acid. 7

7. The product ofclaim 2, wherein said alcohol consists of glycerine and said alkali metalsalt of an amino polyacetic acid consists of the tetrasodium salt of ethylene diamine tetraacetic acid.

8. The product of claim 2, wherein said alcohol consists of mannitol.

9. The product of claim 2, wherein said alcohol consists of triethanol amine.

10. The method of forming a detergent composition of matter which is soluble in water and miscible in alkali metal fatty acid soaps and adapted for use in saline and hard waters which comprises heating an aliphatic polyhydroxy alcohol and a neutral alkali metal salt of a lower alkyl amino polyacetic acid, while in the liquid phase and in the relative proportions within the range of approximately equal amounts up to a large excess of either constituent over the other constituent, for an extended time interval within the range 115-200 C. until the major portion of the water present has been evaporated and the reaction therebetween completed.

11. The method of forming a detergent com position which is soluble in water and miscible in alkali metal fatty acid soaps and adapted for use in saline and hard waters which comprises heating an aqueous solution containing an aliphatic polyhydroxy alcohol and a neutral alkali metal salt of a lower alkyl amino polyacetic acid in the relative proportions ranging from approximately equal amounts. up to a large excess of either constituent over the other constituent, for an extended time interval at temperatures above the boiling point or water but not over about 200 C. efl'ective to remove the major portion oi the said water.

12. The method of claim 11, wherein the heating is continued at a temperature in said range and for a time interval required to obtain a substantially anhydrous liquid phase reaction product.

13. A detergent composition of matter consisting of a mixture of alkali metal fatty acid soap compounds and a reaction product between an aliphatic polyhydroxy alcohol and a neutral alkali metal salt of a lower alkyl amino polyacetic acid, the amount of said reaction product being from relatively small amounts up to approximately equal amounts, by weight, to the fatty acid soap compounds, said reaction product being that formed by the process of claim 10.

14. A detergent composition of matter consisting of a mixture of alkali metal fatty acid soap compounds and a reaction product between glycerine and the tetrasodium salt of ethylene diamine tetraacetic acid formed by the method of claim 10, the amount of said reaction product being from relatively small amounts up to aproximately equal amounts by weight, to the fatty acid soap compounds to impart the desired strong sudsing properties to the mixture in hard and in hard saline waters.

15. A detergent composition of matter consisting of a mixture of alkali metal fatty acid soap compounds and a reaction product between an aliphatic polyhydroxy alcohol and a neutral alkali metal salt of a lower alkyl amino polyacetic acid admixed in the relative proportions providing an excess of the hydroxyl groups in the alcohol over the alkali metal atoms of the said salt, the amount of said reaction product being from relatively small amounts up to approximately equal amounts, by weight, to the fatty acid soap compounds, said reaction product being that formed by the process of claim 10.

16. A detergent composition or matter consisting of a mixture of alkali metal fatty acid soap compounds and a reaction product between an aliphatic polyhydroxy alcohol and a neutral alkali metal salt of a lower alkyl amino polyacetic acid admixed in the relative proportions providing an excess of alkali metal atoms in the salt over the hydroxyl groups of the alcohol, the amount of said reaction product being from relatively small amounts up to approximately equal amounts, by weight, to the fatty acid soap compounds, said reaction product being that formed by the process of claim 10.

FREDERICK C. BERSWORTH. 

